Highly sensitive photodetector based on multijunction 2D-lateral heterostructures

The accessibility of various 2D materials facilitates the fabrication of many atomically thin devices, with a strong motivation towards manipulating quantum light detection. Unlike vertical 2D heterostructures, spatially separated 2D transition metal dichalcogenides (TMDs) lateral heterostructures could offer an exciting platform for probing carrier dynamics of excitons, trions, and their applications in optoelectronics. In this work, we demonstrate CVD-grown multijunction 2D MoSe₂-WSe₂ lateral heterostructures as spectrally tunable photosensors. The photoresponse characteristics of these 2D- phototransistors and other critical device parameters such as responsivity, gain, effective detectivity, and efficiency are evaluated using a tunable laser source in the visible to near-infrared regime. Structural-optical-electrical results are correlated to their macroscale photo-sensing characteristics for efficient photodetector design. This information will enhance the potential in the fields of low-powered electronics, non-volatile memory, and tunable quantum detectors based on lateral heterostructures.